I think there are examples of late 69 Camaro's without the flat bottom.

That was impression I got as well. I have all the GM parts for the ZL2 set up on my Z except the breather so my wife got me a repro from Ricks in 2001 for xmas and it has the ridge on the bottom. I thought I heard somewhere that the repro's where a copy of the late 69 model, but that info was from 12 years ago. I would like to get a flat bottom breather but they are hard to come by and very expensive from what I have seen.

There has always been unconfirmed speculation and theories by many that late August, September and November production end Camaro builds at Norwood were forced to adopt the Chevelle ridged bottom air cleaner base as the stocks of the Camaro flat bottom design were exhausted. Examples put forward as factory originals have not always survived testing and several have turned out to be Chevrolet service replacements which had the Chevelle ridge design after 1970 regardless of application and part numbers. Many "original" were added after factory as the ducted hood became widely popular as an aftermarket speed part and found its way onto 68, and 67 models. Several mid and late September 1969 Camaro builds still have flat bottoms. Anything is possible. We will never know for sure.

I think there are examples of late 69 Camaro's without the flat bottom.

I would like to get a flat bottom breather but they are hard to come by and very expensive from what I have seen.

Parts Place has them on sale now - part # CW10062Z, about $169.00 if I remember correctly. Even features the "notch" on the air snout, which (previously) was always a great way to tell the difference in repops and original ZL2's. My NOS 6485891 has the notch, but is a late production with the ridged bottom. I'll post a pic when I can dig it out -

I have inspected and certified several survivor late build 69Z's Sept & Oct and they have had the ridged bottom. Again this is from first hand experience (not speculation), so based on what I have seen yes the ridged bottom was used/ introduced in late July-early Aug.

Gary (69Z28-RS), I'm curious if you Sept built Z has a ridged bottom, because mine does.

Attached below are a couple of photos of my original cowl air cleaner (09C car - sept '69).-maybe someone else can post a photo of an original 'seamed' bottom' air cleaner??(aren't todays digital cameras convenient???)

Can you take a photo of the full bottom from the bottom? As a comparison to the flat bottom?PS. What did you mean by '4 spot' flame arrester? first time I've heard that term....

Gary,

Be glad to get it back out tomorrow for another shot. "4 spot" refers to 4 dimples evident in the top of the flame arrestor screen - NOS and originals have them, repops don't, as many as I've ever seen. I'll get a better pic of that , too -